Existing known types of apparatus for dispensing flowable materials often provide a single inlet or supply valve that requires separate means for actuating same and which thereby is not directly operable by the amount of source to be applied by the apparatus. This type of apparatus operation requires a synchronization of separate sub-apparatus to try to control the amount of material entering the apparatus relative to that to be dispensed by the apparatus. This tends to cause a lack of unison of action and corresponding flow through the apparatus and which, in turn, detracts from the accuracy and control of flow of material.
Also, existing known types of apparatus for dispensing flowable materials often have a relatively small diameter, and relatively long stroke, piston pump sub-apparatus for pumping material through the apparatus; and a separately actuatable and adjustable much larger cross-sectional area for an ultimate dispensing pump apparatus piston pump structure for dispensing material from the apparatus. In this situation, a small adjustment of the movement of the separately actuated larger area dispensing sub-apparatus can result in a large corresponding variation in the amount of the material ultimately dispensed, defeating the desirable precision often required by a dispensing apparatus.
Some existing known types of apparatus for dispensing flowable material even require a mold plate with a shear plate and knife plate to provide positive cyclic dispensing in lieu of provision of structure to provide precision in the amount of material to be dispensing.
Still further, the existing known types of apparatus for dispensing flowable material usually provide a controlled source of air under pressure for directly operating the material dispensing structures which provide an undesirable source of possible direct contamination of the material to be dispensed, particularly when dispensing food material.
Also, existing known types of apparatus, although having a sub-apparatus dispensing chamber for ultimately dispensing the flowable material, do not provide any appropriate means for diffusing the material throughout the sub-apparatus dispensing chamber to augment the even and accurate dispensing of material, over a given area, from the sub-apparatus ultimate dispensing structure.